Revert "Revert mustardBees/patch-1 because of broken unit tests".. His patch was correct, and unit tests to be corrected.

This reverts commit 47fd3dd69d6255581472f20b5aee215c527cfb34.
Set default field argument for 'show_names' to true. Update unit tests to reflect this new default.
Update assertions arguments order so that 'expected' is always first (to match results language)
Fix grouped field 'show_on_cb' check to first check if property is set.
update .pot linen numbers